Metal alkyl,or alkoxy metal alkyl,ester tetrapropenylsuccinates



United States Patent f 3,485,858 METAL ALKYL, OR ALKOXY METAL ALKYL, ESTER TETRAPROPENYLSUCCINATES Paul Y. C. Gee, Woodbury, and Harry J. Andress, Jr.,

Pitman, N.J., assignors to Mobil Oil Corporation, a corporation of New York No Drawing. Original application Jan. 21, 1965, Ser. No. 427,181. Divided and this application Apr. 3, 1968, Ser. No. 718,344

Int. Cl. (307E 3/06; C07c 69/04; C23f 11/10 US. Cl. 260-4299 2 Claims ABSTRACT OF THE DISCLOSURE Metal alkyl, or alkoxy metal alkyl, ester tetrapropenylsuccinates are employed as corrosion inhibitors in organic compositions.

CROSS-REFERENCE TO RELATED APPLICATION Application Ser. No. 427,181, filed Jan. 21, 1965 (parent application).

BACKGROUND OF THE INVENTION Field of the invention This invention which is a division of our application Ser. No. 427,181, filed Jan. 21, 1965, relates to improved organic compositions and, in one of its aspects relates more particularly to improved organic compositions in the form of liquid hydrocarbons that are normally susceptible of causing deterioration by corrosion. Still more particularly, in this aspect, the invention relates to improved liquid hydrocarbons in the form of petroleum distillate hydrocarbon fuel oils, which, in their uninhibited state, tend to rust metal surfaces, clog screens and to emulsify under the conditions of use.

Description of the prior art It is well known that certain types of organic compositions are normally susceptible of causing deterioration by corrosion when coming into contact with various metal surfaces. For example, it is known that liquid hydrocarbons in the form of fuel oils are prone to form sludge or sediment during periods of prolonged storage. Such sludge or sediment have an adverse effect on burner operation by reason of their tendency to clog screens and noozles, In addition to sediment and sludge which are formed during storage, most fuel oils contain other impurities such as rust, dirt and entrained water. Such sediment, sludge, and other impurities tend to settle out on equipment parts such as nozzles, screens, filters and the like, thereby causing clogging and deterioration and failure of equipment. Another undersirable characteristic of petroleum fuel oils is their tendency to form objectionable emulsions.

A further incident to the sludge formation in the handling of distillate fuels is the breathing of storage vessels. This results in the accumulation of considerable amounts of water in the tanks and thereby causes rusting and consequent deterioration of equipment. Thus, when the fuel is removed for transportation, sufiicient water may be carried along to result in rusting of ferrous metal surfaces in pipelines, tankers, and other equipment.

Heretofore, in the case of fuel oils, and other organic compositions subject to the aforementioned deterioration, it has been the practice to overcome such difficulties through the use of a separate additive for each purpose, i.e. employing a sediment inhibitor, an anti-screen clogging agent, an antirust agent and an emulsion inhibitor. The use of several additives, however, gives rise to problems of additive compatibility, thus restricting the choice of additive combinations. In addition, of course, the use 3,485,858 Patented Dec. 23, 1969 of a plurality of additives unduly increases the cost of the fuel. It is, therefore, highly desirable from a commercial standpoint to overcome the aforementioned difficulties through the use of a single additive agent, which is effective against rusting of metal surfaces, sediment formation, screen and nozzle clogging, and emulsification.

SUMMARY OF THE INVENTION It has now been found that all of the aforementioned difficulties, viz. rusting, sedimentation, screen clogging and emulsification can be overcome by the use of a single additive agent, In this respect, it has now been found that organic compositions, particularly liquid hydrocarbons in the form of petroleum distillate fuel oils, containing minor amounts of metal salts of the group consisting of metal alkyl ester tetrapropenylsuccinates and alkoxy metal alkyl ester tetrapropenylsuccinates, are effectively inhibited, simultaneously, against all of the aforementioned deterioration difliculties.

The present invention, in general, provides improved organic compositions, and preferably liquid hydrocarbons in the form of petroleum distillate fuel oils, containing from about 1 to about 200, and preferably from about 5 to about 50, pounds per 1,000 barrels of liquid hydrocarbon of the aforementioned metal salts, which may comprise either a metal alkyl ester tetrapropenylsuccinate or an alkoxy metal alkyl ester tetrapropenylsuccinate.

The metal salts contemplated herein are, in general, prepared by reacting one mole of a metal alkoxide with from about one to about three moles of tetrapropenylsuccinic anhydride or alkyl esters of tetrapropenylsuccinic acid. The reaction is carried out at an elevated temperature, preferably at a temperature from about C. to about C. The following equations illustrate the general formation of the metal salt products, which are either metal alkyl ester tetrapropenylsuccinates or alkoxy metal alkyl ester tetrapropenylsuccinates:

in which R is a tetrapropenyl group having, for example, the following structure:

CH3 CH3 CH3 CHaCH2CHZ( JHCH2( J=CHC and R' is an alkyl group preferably having from 1 to about 18 carbon atoms.

The organic compounds improved in accordance with the present invention may be any materials that are normally susceptible to deterioration by corrosion or any of the other aforementioned factors, in the manner previously described. A field of specific applicability is the improvement of liquid hydrocarbons in accordance with the present invention, boiling from about 75 F. to about 750 F. Of particular significance is the treatment of petroleum distillate fuel oils having an initial boiling point from about 75 F. to about 135 F., and an end boiling point from about 250 F. to about 750 F. It should be noted, in this respect, that the term distillate fuel oils is not intended to be restricted to straight-run distillate fractions. The distillate fuel oils can be straightrun distillate fuel oils, catalytically or thermally cracked (including hydrocracked) distillate fuel oils, or mixtures of straight-run distillate fuel oils, naphthas and the like, with cracked distillate stocks. Moreover, such fuel oils can be treated in accordance with well known commercial methods, such as acid or caustic treatment, hydrogenation, solvent-refining, clay treatment, and the like.

The distillate fuel oils are characterized by their relatively low viscosity, pour point and the like. The principal property which characterizes the contemplated hydrocarbons, however, is their distillation range. As hereinbefore mentioned, this range will lie between about 75 F. and about 750 F. Obviously, the distillation range of each individual fuel oil will cover a narrower boiling range falling, nevertheless, within the above-specified limits. Likewise, each fuel oil will boil substantially continuously throughout its distillation range.

Particularly contemplated among the fuel oils are Nos. 1, 2 and 3 fuel oils used in heating and as diesel fuel oils, gasoline and the jet combustion fuels. The domestic fuel oils generally conform to the specifications set forth in ASTM Specification D396-48T. Specifications for diesel fuels are defined in ASTM Specification D975-48T. Typical jet fuels are defined in Military Specification MIL-F-5624B.

DESCRIPTION OF SPECIFIC EMBODIMENTS The following examples will serve to illustrate the preparation of the aforementioned metal salts of the present invention, which are either metal alkyl ester tetrapropenylsuccinates or alkoxy metal alkyl ester tetrapropenylsuccinates, and to demonstrate the effectiveness thereof in rendering organic compositions, and particularly liquid hydrocarbons, e.g. petroleum hydrocarbon distillate fuels, thermally stable. It will be understood that it is not intended that the invention be limited to the particular compositions shown or to the operations or manipulations involved. Various modifications of these additives, as previously described, can be employed and will be readily apparent to those skilled in the art.

Example 1.-A mixture of 133 grams (0.5 mole) of tetrapropenylsuccinic anhydride, 6.08 grams (0.25 mole) of magnesium in the form of a magnesium methylate solution and 139 grams of a solvent-refined petroleum mineral oil obtained from a Mid-Continent crude, as a diluent, was gradually heated to 140 C, with stirring, and was held at that temperature until all the methanol had distilled out, viz. for a period of about one hour. The resulting reaction product was filtered through Hyflo- Super-Cel clay. The final filtered product, viz. the magnesium methyl ester tetrapropenylsuccinate, containing 50 percent of the aforementioned diluent, was clear and fluid at room temperature.

Analysis.-Percent Mg: Estimated, 2.1. Found, 1.95.

Example 2.A mixture of 133 grams (0.5 mole) of tetrapropenylsuccinic anhydride, 12.16 grams (0.5 mole) of magnesium in the form of a magnesium methylate solution and grams of the same diluent employed in Example 1, was gradually heated to 140 C. with stirring, and was held at that temperature until the methanol stopped coming over, viz. for a period of about two hours. The resulting reaction product, being viscous at room temperature, was diluted with an additional 145 grams of the above-described mineral oil diluent and filtered through the aforementioned clay. The final filtered product, viz. the methoxy magnesium methyl ester tetrapropenylsuccinate, containing 66 /3 percent of the aforementioned mineral oil diluent, was clear and fluid at room temperature.

Analysis.--Percent Mg: Estimated, 2.7. Found, 2.63.

Example 3.A mixture of 266 grams (1 mole) of tetrapropenylsuccinic anhydride, diluted with 668 grams of the same mineral oil diluent employed in Example 1, and 68.5 grams (0.5 mole) of barium in the form of a barium methylate solution was gradually heated to C. and was held at that temperature until the methanol stopped coming over, viz. for a period of about two hours. The resulting reaction product was filtered through the aforementioned clay. The final filtered product, viz. the barium methyl ester tetrapropenylsuccinate, containing 66% percent of the aforementioned mineral oil diluent, was clear and fluid at room temperature.

Analysis.Percent Ba: Estimated, 6.6. Found, 6.7.

Example 4.A mixture of 266 grams (1 mole) of tetrapropenylsuccinic anhydride, diluted with 300 cc. of xylene, and 23 grams (1 mole) of sodium in the form of a sodium methylate solution, was gradually heated to 150 C., and was held at that temperature for two hours to form the sodium methyl ester tetrapropenylsuccinate. To the sodium methyl ester tetrapropenylsuccinate thus formed, was added at room temperature with stirring, 78 grams (0.5 mole+15% excess) of zinc chloride, previously dissolved in 300 cc. of methanol. Th5 mixture was gradually heated to 150 C., and was held at that temperature for a period of two hours to insure the complete formation of the zinc salt. The resulting reaction product, being viscous at room temperature, was diluted with about 700 cc. of benzene, filtered through the aforementioned clay, and distilled to 150 C. under house vacuum. The residue, was found to weigh 323 grams, theory 329 grams, and was diluted with 323 grams of the above-described mineral oil diluent. The final product, viz. the zinc methyl ester tetrapropenylsuccinate, containing 50 percent of the aforementioned mineral oil diluent, was clear and fluid at room temperature.

Analysis.Percent Zn: Estimated, 5.4. Found, 5.37.

Example 5.A mixture of 133 grams (0.5 mole) of tetrapropenylsuccinic anhydride, diluted with 150 cc. of Xylene, and 11.5 grams (0.5 mole) of sodium in the form of a sodium methylate solution, was gradually heated to 150 C. with stirring, and was held at that temperature for a period of two hours to form the sodium methyl ester tetrapropenylsuccinate. To the sodium methyl ester tetrapropenylsuccinate thus formed, was added at room temperature with stirring 33 grams (0.25 mole+15% ex cess) of calcium chloride, previously dissolved in 200 cc.

of methanol. The mixture was gradually heated to 150 C., and was held at that temperature for a period of two hours to form the calcium methyl ester tetrapropenylsuccinate. The resulting reaction product, being viscous at room temperature, was diluted with benzene, filtered through the aforementioned clay and distilled to 150 C. under house vacuum. The residue was diluted with 286 grams of the above-described mineral oil diluent. The final product, viz. the calcium methyl ester tetrapropenylsuccinate, containing approximately 66% percent of the aforementioned mineral oil diluent, was clear and fluid at room temperature.

Analysis.--'Percent Ca: Estimated, 2.3. Found, 2.9-.

Example 6.-A mixture of 133 grams (0.5 mole) of tetrapropenylsuccinic anhydride, 100 grams (0.5 mole) of tridecyl alcohol, 2,3 grams (1%) of p-toluene sulfonic acid monohydrate and 200 cc. of xylene was stirred at about 140 C. for a period of three hours to form the tridecyl ester tetrapropenylsuccinic acid. To the tridecyl ester tetrapropenylsuccinic acid was added at room temperature with stirring 11.5 grams (0.5 mole) of sodium in the form of a sodium methylate solution. The mixture was gradually heated to 150 C. to form the sodium tridecyl ester tetrapropenylsuccinate. To the sodium tridecyl ester tetrapropenylsuccinate was added at room temperature with stirring 44 grams (0.25 mole+ grams excess) of zinc chloride, previously dissolved in 200 cc. of methanol. This mixture was gradually heated to 150 C. and was held at that temperature for a period of one hour to form the zinc tridecyl ester tetrapropenylsuccinate. The reaction mixture, being viscous at room temperature, was diluted with benzene, filtered through the aforementioned clay and distilled to 150 C. under house vacuum. The residue which weighed 241 grams, theory 249 grams, was diluted with 241 grams of the above-described mineral oil diluent. The final product, viz. the zinc tridecyl ester tetrapropenylsuccinate, which contained 50 percent of the aforementioned mineral oil diluent was clear and fluid at room temperature.

Analysis.Percent Zn: Estimated, 3.37. Found, 3.70.

Example 7.-A mixture of 133 grams (0.5 mole) of tetrapropenylsuccinic anhydride, 121 grams (0.5 mole) of hexadecyl alcohol, 2.6 grams (1%) of p-toluene sulfonic acid monohydrate and 125 cc. of toluene, was stirred at 140 C. for a period of three hours to form the hexadecyl ester tetrapropenylsuccinic acid. To the hexadecyl ester tetrapropenylsuccinic acid thus formed, was added at room temperature with stirring 11.5 grams (0.5 mole) of sodium in the form of a sodium methylate solution. The mixture was gradually heated to 150 C. to form the sodium hexadecyl ester tetrapropenylsuccinate. To the sodium hexadecyl ester tetrapropenylsuccinate thus formed was added at room temperature with stirring 44 grams (0.25 mole+10 grams excess) of zinc chloride previously dissolved in 200 cc. of methanol. The mixture was then gradually heated to 150 C. and was held at that temperature for a period of two hours to insure the complete formation of the zinc hexadecyl ester tetrapropenylsuccinate. The resulting reaction product, being viscous at room temperature, was diluted with benzene, filtered through the aforementioned clay and distilled to 150 C. under house vacuum. The residue weighed 260 grams, theory 266 grams, and was diluted with 260 grams of the aforementioned mineral oil diluent. The final product, viz. the zinc hexadecyl ester tetrapropenylsuccinate, containing 50 percent of the aforementioned mineral oil diluent, was clear and fluid at room temperature.

Analysis.--Percent Z11: Estimated, 3.1. Found, 3.64.

Example 8.A mixture of 133 grams (0.5 mole) of tetrapropenylsuccinic anhydride, diluted with 266 grams of xylene, and 4.5 grams mole) of aluminum in the form of an aluminum methylate solution, was gradually heated to distill out the methanol, with stirring. The resulting reaction mixture became viscous at 80 C. About 30 cc. of water, being added dropwise, made the reaction mixture fluid again. This reaction mixture was then gradually heated to 140 C. to distill out the methanol, and was then filtered through the aforementioned clay. The final product, viz. the aluminum methyl ester tetrapropenylsuccinate, containing approximately 66 /3 percent xylene, was clear and fluid at room temperature.

Analysis.-Percent Al: Estimated, 1.1. Found, 1.5.

The eificacy of the aforementioned metal salts were demonstrated by the following tests.

SCREEN CLOGGING The anti-screen clogging characteristics of a fuel oil were determined as follows: The test is conducted using a Sundstrand V3 or S1 home fuel oil burner pump with a self-contained -mesh Monel metal screen. About 0.05 percent, by weight, of naturally-formed fuel oil sediment, composed of fuel oil, water, dirt, rust, and organic sludge is mixed with 10 liters of the fuel oil. This mixture is circulated by the pump through the screen for 6 hours. Then, the sludge deposit on the screen is washed off with normal pentane and filtered through a tared Gooch crucible. After drying, the material in the Gooch crucible is washed with a 50-50 (volume) acetone-methanol mixture. The total organic sediment is obtained by evaporating the pentane and the acetone-methanol filtrates. Drying and weighing the Gooch crucible yields the amounts of inorganic sediment. The sum of the organic and inorganic deposits on the screen can be reported in milligrams recovered or converted into percent screen clogging.

The metal salt additives of the aforementioned Examples 1 through 8 were incorporated in a fuel oil blend comprising, by weight, approximately 60% distillate stock obtained from continuous catalytic cracking and approximately 20% straight-run distillate stock, having a boiling range of from about 320 F. to about 640 F., and being a practical No. 2 fuel oil. The results obtained are set forth in the following Table I.

TABLE I.-SCREEN CLOGGING TESTS The test used to determine the sedimentation characteristics of the fuel oils is the F. storage test. In this test, a SOO-milliliter sample of the fuel oil under test is placed in a convected oven maintained at 110 F. for a period of 12 Weeks. Then, the sample is removed from the oven and cooled. The cooled sample is filtered through a tared asbestos filter (Gooch crucible) to remove insoluble matter. The weight of such matter in milligrams is reported as the amount of sediment. A sample of the blank, uninhibited oil is run along with a fuel oil blend under test. The effectiveness of a fuel oil containing an inhibitor is determined by comparing the weight of sediment formed in the inhibited oil with that formed in the uninhibited oil.

Additives described in the examples were blended in test fuel oil and the blends were subjected to the 110 F. storage test. The test fuel oil was a blend of 80 percent distillate stock obtained from continuous catalytic cracking and 20 percent straight-run distillate stock. It has a boiling range of between about 320 F. and about 640 F. and is a typical No. 2 fuel oil. The results obtained are set forth in the following Table II.

The method used for testing anti-rust properties of gasolines was the ASTM Rust Test D-665 operated for 48 hours at 80 F. using distilled water. This is a dynamic test that indicates the ability to prevent rusting of ferrous metal surfaces in pipelines, tubes, etc. Blends of the additives described in the fuel oil, such as employed in accordance with the tests disclosed in Tables I and II, were subjected to the ASTM Rust Test D-665. The results obtained are set forth in the following Table III.

TABLE TIL-ASTM RUST TEST D-665 Concn., Rust Test p.p.n1. Result Fail.

25 Pass.

D0. 25 Do.

Inhibitors Blank fuel blend Blank fuel blend plus- Do. .25 D0. Do.

Additional mineral oil blends were prepared. Each blend contained a small amount of the aforementioned additives described in the examples. The base oil employed was a highly solvent-refined mineral lubricating oil having 31 API gravity and a Saybolt Universal viscosity of 150 seconds at 100 F. This is a typical steam turbine lubricating oil. These blends Were subjected to the aforementioned ASTM Rust Test D665. The results obtained are set forth in the following Table IV.

TABLE IV.-ASTl /I RUST TEST D-605 C0ncn., Rust Test Inhibitors wt. percent Result Blank light turbine oil 0 Fail.

Blarik light turbine oil plus- It will be apparent, from the data set forth in Tables I through IV, that the metal alkyl ester tetrapropenylsuccinates and the alkoxy metal alkyl ester tetrapropenylsuccinates of the present invention are highly effective in reducing sedimentation, screen clogging, and in inhibiting corrosion of metal surfaces. As will be understood, results will vary among the specific materials employed. In order to accomplish any given improvement, many of the additives can be used in relatively minor proportions, as, for ex ample, in the prevention of corrosion. If, on the other hand, it is desired to accomplish all the aforementioned beneficial results, this can be carried out at the practical addiive concentrations of from 5 to about 50 pounds per 1,000 barrels of liquid hydrocarbon.

.Although the present invention has been. described with t preferred embodiments, it will be understood that various modifications and adaptations thereof may be resorted to wihout departing from the spirit and scope of the. invention.

We claim:

1. A compound selected from the group consisting of metal alkyl ester tetrapropenylsuccinates and alkoxy metal alkyl ester tetrapropenylsuccinate's, the metal component of said tetrapropenylsuccinates being selected from the class consisting of Groups I, II and III of Periodic Tableof the Elements.

2. A compound as defined in claim 1 wherein the metal of said tetrapropenylsuccinates is selected from the group consisting of magnesium, barium, zinc, calcium and alumi- 'num.

References Cited UNITED STATES PATENTS TOBIAS E. LEVOW, Primary Examiner H. M. S. SNEED, Assistant Examiner US. Cl. X.R.

'zgy g UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Pat zent No. 3, 5, 5 Dated December 3, 1969 Inventor(s) Paul Y. C. Gee and Harry J. AndressI Jr.

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 2, line 58, for "1A" read ---Al-- Column 5, line 16, for "2,3" read ---2.3---

Column 5, line 71, for "1/16 mole" read ---l/6 mo1e-- Column 8, line 13, for "addiive" read ---additive--- SIGNED AND SEALED JUN 2 3 1970 6 Amen wmnu E. .m. MM (:Z Comissioner of Patents 

